On March 25, the reactor of Power Unit 2 of Belarus NPP (general designer and general contractor is Rosatom State Corporation Engineering Division) was brought to minimum controllable power level. At 19:42 (Moscow time), the neutron flux was registered for the first time, and controlled self-sustained nuclear reactor began.
Achievement of the minimum controllable power level (less than 1% of the rated power) makes it possible to proceed to the final part of tests of the Power Unit physical start-up stage. To confirm compliance with the design and clarify the rated neutron and physical characteristics of the reactor first fuel loading, the specialists will take measurements of the actual state of the core. Reliability of functioning of protections, interlocking and the entire nuclear physical control and nuclear safety systems of the reactor plant will also be checked.
The results of the tests will be submitted to the authorized bodies of the Republic of Belarus for obtaining a permit for the Unit power start-up, after which gradual increase of the power will begin. Simultaneously with the performance of all the necessary physical start-up operations, specialists will continue the planned preparation for the subsequent stages of the start-up works – power start-up and trial operation.
For reference:
Belarus NPP with two VVER-1200 reactors with a total capacity of 2 400 MW is being built in Ostrovets (the Republic of Belarus). A Russian generation III+ design has been selected for the first NPP in Belarus, which fully complies with the international standards and safety requirements of the International Atomic Energy Agency (IAEA). Power Unit 1 of Belarus NPP, which became the first nuclear facility of the latest III+ generation built abroad using the Russian technologies, was put into commercial operation on June 10, 2021.
The ROSATOM Engineering Division unites the leading companies of the nuclear industry, namely: Atomstroyexport JSC (Moscow, Nizhny Novgorod, branches in Russia and abroad), Joint Design Institute - Atomenergoproekt JSC (Moscow, Nizhny Novgorod, St. Petersburg branches - design institutes, branches in Russia and abroad, R&D branches) and subsidiary construction organizations. The Engineering Division ranks first in the world by the order portfolio and the number of NPPs constructed simultaneously across the world. About 80% of the Division’s revenues originate from foreign projects. The Engineering Division implements construction projects for high-power NPPs in Russia and across the world, renders a full range of EPC, EP, EPC(M) services including project management and design activities, and develops Multi-D technologies for the management of complex engineering facilities. The Division relies on the achievements of the Russian nuclear industry and innovative state-of-the-art technologies. www.ase-ec.ru
ROSATOM is the recognized global leader and the only company in the world implementing serial construction of nuclear power plants abroad. Globally, 106 Russian-designed nuclear power facilities have been built, including 80 power units with VVER type reactors. To date, ROSATOM international order portfolio comprises 34 VVER units in 11 countries at various stages of implementation.

Source: Communications Division of ROSATOM Engineering Division